Adsorptive flotation removal of sodium tripolyphosphate from waste liquid

ABSTRACT

Techniques are generally described herein for the removal of sodium tripolyphosphate from a waste liquid. Embodiments include, but are not limited to, methods, apparatuses, systems, and articles of manufacture. Other embodiments may also be disclosed and claimed. Some techniques described herein include adding a phosphate binder to the waste liquid including sodium tripolyphosphate to cause the sodium tripolyphosphate to adsorb to the phosphate binder, and aerating the waste liquid to form bubbles in the waste liquid and to cause particles of the phosphate binder having the sodium tripolyphosphate adsorbed thereto to adhere to the bubbles and rise to a top surface of the waste liquid.

BACKGROUND

Phosphates may be used as a detergent builder for chelating and removingvarious ions present in hard water. The removal of hard water ions mayallow for a reduction in the concentration of surfactant necessary fordetersive action. Phosphates, however, have been implicated ineutrophication, an increase in nutrients in water bodies (lakes,streams, and the like) sometimes resulting in excessive plant growth. Asdead plant matter decomposes, dissolved oxygen may be reduced, whichstarves fish and other organisms.

BRIEF DESCRIPTION OF THE DRAWINGS

Subject matter is particularly pointed out and distinctly claimed in theconcluding portion of the specification. The foregoing and otherfeatures of the present disclosure will become more fully apparent fromthe following description and appended claims, taken in conjunction withthe accompanying drawings. Understanding that these drawings depict onlyseveral embodiments in accordance with the disclosure and are,therefore, not to be considered limiting of its scope, the disclosurewill be described with additional specificity and detail through use ofthe accompanying drawings, in which:

FIG. 1 is a block diagram of an example system for removing sodiumtripolyphosphate from a waste liquid;

FIG. 2 is a simplified representation of an example separation cell andthe sodium tripolyphosphate removal process;

FIG. 3 is a flow diagram illustrating some of the operations associatedwith an example method for removing sodium tripolyphosphate from a wasteliquid;

FIG. 4 is a block diagram of an example computing device forfacilitating removal of sodium tripolyphosphate from a waste liquid; and

FIG. 5 is a block diagram of an example computer program product forfacilitating removal of sodium tripolyphosphate from a waste liquid;

all arranged in accordance with various embodiments of the presentdisclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. The illustrative embodiments described in thedetailed description, drawings, and claims are not meant to be limiting.Other embodiments may be utilized, and other changes may be made,without departing from the spirit or scope of the subject matterpresented herein. It will be readily understood that the aspects of thepresent disclosure, as generally described herein, and illustrated inthe Figures, can be arranged, substituted, combined, separated, anddesigned in a wide variety of different configurations, all of which areexplicitly contemplated herein.

The removal of sodium tripolyphosphate from a waste liquid is disclosed.Embodiments include, but are not limited to, methods, apparatuses,systems, and articles of manufacture. Other embodiments may also bedisclosed and claimed.

Various embodiments may include adding a phosphate binder to a wasteliquid including phosphates, such as, for example, waste detergentwater, and aerating the liquid to cause particles of the phosphatebinder having sodium tripolyphosphate adsorbed thereto to rise to a topsurface of the liquid. The particles may be removed from the top surfaceof the waste liquid and are then available for solid-waste disposal. Theeffluent liquid having sodium tripolyphosphate removed therefrom maythen be disposed of as standard wastewater or may be reclaimed with orwithout further treatment.

FIG. 1 is a block diagram of an example system for removing sodiumtripolyphosphate from a waste liquid, arranged in accordance with atleast some embodiments of the present disclosure. A basic configurationof system 100 may include a controller 102, a separation cell 104, awaste liquid source 106, and a power source 108, all coupled togetherand generally configured as illustrated.

Separation cell 104 may be configured to remove sodium tripolyphosphatefrom a waste liquid according to the various methods described herein. Aphosphate binder may be provided via inlet 118 to liquid includingsodium tripolyphosphate provided via inlet 120. The phosphate binder mayadsorb to sodium tripolyphosphate in the waste liquid and provided totank 114 via inlet 142 as illustrated. In various embodiments, thephosphate binder may additionally or alternatively adsorb to sodiumtripolyphosphate in tank 114. A pump 122 may be configured to route thewaste liquid to tank 114. The waste liquid in tank 114 may be aerated byaerator 116 to cause particles of the phosphate binder having sodiumtripolyphosphate adsorbed thereto to rise to a top surface of the wasteliquid in separation cell 104, as described more fully herein. A skimmer112 may be configured to then remove the particles that rise to the topsurface of the waste liquid. The removed particles of phosphate binderhaving sodium tripolyphosphate adsorbed thereto may then be madeavailable for solid-waste disposal.

The waste liquid including phosphates may be received, directly orindirectly, from a source of waste liquid including sodiumtripolyphosphate 106. In various embodiments, source 106 may comprise awaste liquid source (e.g., a dishwasher, a washing machine, or thelike). Waste liquid may comprise, for example, waste wash water. Invarious instances, waste wash water may be a vastly different mediumthan other types of liquid such as seawater. For example, the phosphatein waste detergent water may include sodium tripolyphosphate with thechemical formula of Na₅P₃O₁₀, which may eventually be broken down (i.e.,hydrolyzed) biochemically by bacteria in sewage pipes, water bodies,etc., to phosphate, PO₄ ³⁻. In other words, upstream of sewage, the“phosphate” may not be PO₄ ³⁻, but may instead be Na₅P₃O₁₀. In addition,waste wash water may contain a large amount of surfactants, which maynot be present in other types of waste liquid, and/or may contain one ormore components that may compete with sodium tripolyphosphate foradsorption sites on whatever phosphate binder is used.

In various embodiments, the waste liquid having sodium tripolyphosphateremoved according to the embodiments described herein (“effluentliquid”) may be reclaimed for further use. Reclaimed liquid may besubjected to a wastewater treatment for removing physical, chemical, orbiological contaminants prior to and/or after removal of sodiumtripolyphosphate. As illustrated, for example, system 100 may include awastewater treatment apparatus 124, and the effluent liquid may berouted from tank 114 to the wastewater treatment apparatus 124 fortreatment. The reclaimed liquid may be routed to another component(e.g., source 106 or another component) within system 100 for use.Additionally or alternatively, the reclaimed liquid and/or the effluentliquid may be routed outside system 100 for disposal or further useand/or treatment.

Controller 102 may be any device suitable for monitoring, adjusting,and/or controlling a process of removing sodium tripolyphosphate from awaste liquid according to the various methods described herein. Forexample, controller 102 may be a computing device (e.g., a computersystem, a microprocessor, a microcontroller, etc.) or an embeddedcontroller (e.g., an Application Specific Integrated Circuit (ASIC), orsome other equivalent). Controller 102 may include a control process 110that includes one or more instructions for monitoring, adjusting, and/orcontrolling the process of removing sodium tripolyphosphate from a wasteliquid according to the various methods described herein. As an example,control process 110 may include instructions for implementing a methodfor removing sodium tripolyphosphate from a waste liquid, comprisingadding a phosphate binder, via inlet 118, to liquid including sodiumtripolyphosphate received by tank 114 from source 106, via inlet 120,and aerating the waste liquid to cause particles of the phosphate binderhaving the sodium tripolyphosphate adsorbed thereto to rise to a topsurface of the waste liquid in tank 114. Various instructions processedby controller 102 may include operating power source 108 to controlsignals (e.g., voltage, current, etc.) delivered to the separation cell104, operating tank 114 to receive the waste liquid including the sodiumtripolyphosphate, the phosphate binder, or both, and to output theeffluent liquid having sodium tripolyphosphate removed therefrom,operating aerator 116 to aerate the liquid in separation cell 104,operating skimmer 112 to remove the particles from the top surface ofthe waste liquid in tank 114, and/or any monitoring, adjusting, and/orcontrolling other control(s) associated with removal of phosphates froma waste liquid in separation cell 104.

A simplified representation of an example separation cell and the sodiumtripolyphosphate removal process for at least some embodiments of thepresent disclosure is illustrated in FIG. 2. As illustrated, wasteliquid 226 including sodium tripolyphosphate 228 (depicted as solidsquares) may be provided to tank 114 via an inlet 120, and a phosphatebinder 230 (depicted as triangles) may be provided to the waste liquid226 via an inlet 118. For various embodiments, phosphate binder 230 maybe additionally or alternatively provided directly to tank 114 havingwaste liquid 226 therein. The phosphate binder 230 may be held by ahopper 232 or any suitable receptacle for holding and routing thephosphate binder 228 to waste liquid 226 and/or tank 114.

Sodium tripolyphosphate 228 may adsorb to phosphate binder 230 to formparticles 236 that are insoluble in water. A suitable phosphate binder230 may comprise a salt of at least one of magnesium, lanthanum, nickel,cadmium, iron, zinc, cobalt, strontium, barium, or manganese, and theselected phosphate binder 230 may be one being sufficiently insoluble inwaste liquid 226 so as to facilitate removal of particles 236 from thetop surface of the waste liquid 226. Calcium carbonate, for example, maybe used as phosphate binder 230. Other suitable salts may includecalcium acetate, magnesium carbonate, lanthanum carbonate, calciumacetate, magnesium carbonate, lanthanum carbonate, nickel carbonate,cadmium carbonate, iron carbonate, zinc carbonate, cobalt carbonate,strontium carbonate, barium carbonate, or manganese carbonate, ormixtures thereof.

Particles 236, comprised of phosphate binder 230 having sodiumtripolyphosphate 228 adsorbed thereto, may be introduced to tank 114 viainlet 142, as illustrated, and particles 236 may be removed from wasteliquid 226 by causing particles 236 to be carried to a top surface ofwaste liquid 226 by one or more gas bubbles 238 (depicted as circles) toform a froth. In principle, and without being bound by theory, sodiumtripolyphosphate 230 adsorb to phosphate binder 230, and phosphatebinder 230 in turn adheres to the surfaces of the gas bubbles 238 due atleast in part to the insolubility of phosphate binder 230 in wasteliquid 226. As the gas bubbles 238 float to the top surface of the wasteliquid 226, phosphate binder 230 having sodium tripolyphosphate 228adsorbed thereto are in effect carried to the top surface of wasteliquid 226. Particles 236 may then be skimmed from the top surface ofwaste liquid 226 by a skimmer 240. Gas bubbles 238 may be formed byintroducing air, nitrogen, oxygen, or another suitable gas to the wasteliquid via an inlet 234, and an aerator 116 may be configured to causethe gas to be introduced to waste liquid 226 as gas bubbles 238 in wasteliquid 226. Any suitable apparatus may be used for aerating waste liquid226 including, for example, a sparger (as illustrated), an injector, anaspirator, a nozzle, a bubble generator, or the like. Particles 236 maythen be skimmed from the top surface of waste liquid 226 by a skimmer240 or other suitable method for removing particles 236 from the topsurface of waste liquid 226.

FIG. 3 is a flow diagram illustrating some of the operations associatedwith an example method for removing sodium tripolyphosphate from a wasteliquid, arranged in accordance with at least some embodiments of thepresent disclosure. It should be noted that although the method isillustrated as a series of sequential steps, the method is notnecessarily order dependent. Moreover, methods within the scope of thisdisclosure may include more or fewer steps than that illustrated.

Turning now to FIG. 3, with continued reference to system 100illustrated in FIG. 1, method 300 may include one or more functions,operations, or actions as is illustrated by block 302, block 304, block306, and/or block 308. Processing for method 300 may start with block302 (“Provide a waste liquid including sodium tripolyphosphate”). Theliquid including sodium tripolyphosphate may be generated by cleaningapparatus 106 of system 100, or may be provided from another source asdescribed herein.

From block 302, method 300 may proceed to block 304 (“Add a phosphatebinder to the waste liquid to cause sodium tripolyphosphate to adsorb tothe phosphate binder”), and then to block 304 (“Aerate the waste liquidto form bubbles in the waste liquid and to cause particles of thephosphate binder having the sodium tripolyphosphate adsorbed thereto toadhere to the bubbles and rise to a top surface of the waste liquid”).The phosphate binder may be routed to the waste liquid by hopper 232 ofseparation cell 104 or by another suitable apparatus, and the wasteliquid may be aerated using aerator 116 of separation cell 104 oranother suitable apparatus for providing gas bubbles in the wasteliquid. In some embodiments, for example, the phosphate binder may bemanually added to the waste liquid. The phosphate binder may be routedto the waste liquid prior to aeration, during aeration, or both.

From block 306, method 300 may proceed to block 308 (“Remove theparticles from the top surface of the waste liquid”). As describedherein, the bubbles provided by the aeration may carry the particles tothe top surface forming a froth that may be removed for solid-wastedisposal or other use. Skimmer 240 may be suitable for removing theparticles.

FIG. 4 is a block diagram illustrating an example computing deviceconfigured for facilitating removal of sodium tripolyphosphate from awaste liquid in accordance with at least some embodiments of the presentdisclosure. In a basic configuration 401, computing device 400 typicallyincludes one or more processors 410 and system memory 420. A memory bus430 may be used for communicating between processor 410 and systemmemory 420. In various embodiments, computing device 400 may be adaptedto monitor, adjust, and/or control a process of removing sodiumtripolyphosphate from a waste liquid as described herein. Computingdevice 400 may be implemented, for example, as controller 102 of system100 of FIG. 1.

Depending on the desired configuration, processor 410 may be of any typeincluding but not limited to a microprocessor (μP), a microcontroller(μC), a digital signal processor (DSP), or any combination thereof.Processor 410 may include one more levels of caching, such as a levelone cache 411 and a level two cache 412, a processor core 413, andregisters 414. An example processor core 413 may include an arithmeticlogic unit (ALU), a floating point unit (FPU), a digital signalprocessing core (DSP Core), or any combination thereof. An examplememory controller 415 may also be used with processor 410, or in someimplementations memory controller 415 may be an internal part ofprocessor 410.

Depending on the desired configuration, system memory 420 may be of anytype including but not limited to volatile memory (such as RAM),non-volatile memory (such as ROM, flash memory, etc.) or any combinationthereof. System memory 420 may include an operating system 421, one ormore applications 422, and program data 424. Application 422 may includeprogramming instructions providing logic 492 to implement the abovedescribed controlling, adjusting, and/or monitoring of a process ofremoving sodium tripolyphosphate from a waste liquid as describedherein. Program data 424 may include the applicable process parameters494 and related values.

Computing device 400 may have additional features or functionality, suchas additional interfaces to facilitate communications between the basicconfiguration 401 and any required devices and interfaces. For example,a bus/interface controller 440 may be used to facilitate communicationsbetween the basic configuration 401 and one or more data storage devices450 via a storage interface bus 441. Data storage devices 450 may beremovable storage devices 451, non-removable storage devices 452, or acombination thereof. Examples of removable storage and non-removablestorage devices include magnetic disk devices such as flexible diskdrives and hard-disk drives (HDD), optical disk drives such as compactdisk (CD) drives or digital versatile disk (DVD) drives, solid statedrives (SSD), and tape drives to name a few. Example computer storagemedia may include volatile and nonvolatile, removable and non-removablemedia implemented in any method or technology for storage ofinformation, such as computer readable instructions, data structures,program modules, or other data.

System memory 420, removable storage 451 and non-removable storage 452are all examples of computer storage media. Computer storage mediaincludes, but is not limited to, RAM, ROM, EEPROM, flash memory or othermemory technology, CD-ROM, digital versatile disks (DVD) or otheroptical storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or any other medium which maybe used to store the desired information and which may be accessed bycomputing device 400. Any such computer storage media may be part ofdevice 400.

Computing device 400 may also include an interface bus 442 forfacilitating communication from various interface devices (e.g., outputinterfaces, peripheral interfaces, and communication interfaces) tobasic configuration 401 via bus/interface controller 440. Example outputdevices 460 include a graphics processing unit 461 and an audioprocessing unit 462, which may be configured to communicate to variousexternal devices such as a display or speakers via one or more A/V ports463. Example peripheral interfaces 470 include a serial interfacecontroller 471 or a parallel interface controller 472, which may beconfigured to communicate with external devices such as input devices(e.g., keyboard, mouse, pen, voice input device, touch input device,etc.) or other peripheral devices (e.g., printer, scanner, etc.) via oneor more I/O ports 473. An example communication device 480 includes anetwork controller 481, which may be arranged to facilitatecommunications with one or more other computing devices 490 over anetwork communication link via one or more communication ports 482.

The network communication link may be one example of communicationmedia. Communication media may typically be embodied by computerreadable instructions, data structures, program modules, or other datain a modulated data signal, such as a carrier wave or other transportmechanism, and may include any information delivery media. A “modulateddata signal” may be a signal that has one or more of its characteristicsset or changed in such a manner as to encode information in the signal.By way of example, and not limitation, communication media may includewired media such as a wired network or direct-wired connection, andwireless media such as acoustic, radio frequency (RF), microwave,infrared (IR) and other wireless media. The term computer readable mediaas used herein may include both storage media and communication media.

The computing device 400 may be implemented as a portion of a small-formfactor portable (or mobile) electronic device such as a cell phone, apersonal data assistant (PDA), a personal media player device, awireless web-watch device, a personal headset device, an applicationspecific device, or a hybrid device that include any of the abovefunctions. Computing device 400 may also be implemented as a personalcomputer including both laptop computer and non-laptop computerconfigurations.

FIG. 5 is a block diagram of an example computer program product forfacilitating removal of sodium tripolyphosphate from a waste liquid,arranged in accordance with at least some embodiments of the presentdisclosure. In an example, as shown in FIG. 5, the computer programproduct 500 may include a signal-bearing medium 502 that may includecomputer-executable instructions 504. Computer-executable instructions504 may be for adding a phosphate binder to a waste liquid includingsodium tripolyphosphate to cause sodium tripolyphosphate to adsorb tothe phosphate binder. Computer-executable instructions 504 may also befor aerating the waste liquid to form bubbles in the waste liquid and tocause particles of the phosphate binder having the sodiumtripolyphosphate adsorbed thereto to adhere to the bubbles and rise to atop surface of the waste liquid.

Also depicted in FIG. 5, computer program product 500 may include one ormore of a computer-readable medium 506, a recordable medium 508, and acommunications medium 510. The dotted boxes around these elements depictdifferent types of mediums included within, but not limited to, asignal-bearing medium 502. These types of mediums may distributecomputer-executable instructions 504 to be executed by logic.Computer-readable medium 506 and recordable medium 508 may include, butare not limited to, a flexible disk, a hard disk drive (HDD), a CompactDisc (CD), a Digital Video Disk (DVD), a digital tape, a computermemory, etc. Communications medium 510 may include, but is not limitedto, a digital and/or an analog communication medium (e.g., a fiber-opticcable, a waveguide, a wired communication link, a wireless communicationlink, etc.).

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art may translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations may be expressly set forth herein for sakeof clarity.

It will be understood by those within the art that, in general, termsused herein, and especially in the appended claims (e.g., bodies of theappended claims) are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to inventions containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should typically be interpreted to mean “atleast one” or “one or more”); the same holds true for the use ofdefinite articles used to introduce claim recitations. In addition, evenif a specific number of an introduced claim recitation is explicitlyrecited, those skilled in the art will recognize that such recitationshould typically be interpreted to mean at least the recited number(e.g., the bare recitation of “two recitations,” without othermodifiers, typically means at least two recitations, or two or morerecitations). Furthermore, in those instances where a conventionanalogous to “at least one of A, B, and C, etc.” is used, in generalsuch a construction is intended in the sense one having skill in the artwould understand the convention (e.g., “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). In those instances where aconvention analogous to “at least one of A, B, or C, etc.” is used, ingeneral such a construction is intended in the sense one having skill inthe art would understand the convention (e.g., “a system having at leastone of A, B, or C” would include but not be limited to systems that haveA alone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). It will be furtherunderstood by those within the art that virtually any disjunctive wordand/or phrase presenting two or more alternative terms, whether in thedescription, claims, or drawings, should be understood to contemplatethe possibilities of including one of the terms, either of the terms, orboth terms. For example, the phrase “A or B” will be understood toinclude the possibilities of “A” or “B” or “A and B.”

Various operations may be described as multiple discrete operations inturn, in a manner that may be helpful in understanding embodiments;however, the order of description should not be construed to imply thatthese operations are order-dependent. Also, embodiments may have feweroperations than described. A description of multiple discrete operationsshould not be construed to imply that all operations are necessary.Also, embodiments may have fewer operations than described. Adescription of multiple discrete operations should not be construed toimply that all operations are necessary.

In addition, where features or aspects of the disclosure are describedin terms of Markush groups, those skilled in the art will recognize thatthe disclosure is also thereby described in terms of any individualmember or subgroup of members of the Markush group.

As will be understood by one skilled in the art, for any and allpurposes, such as in terms of providing a written description, allranges disclosed herein also encompass any and all possible subrangesand combinations of subranges thereof. Any listed range can be easilyrecognized as sufficiently describing and enabling the same range beingbroken down into at least equal halves, thirds, quarters, fifths,tenths, etc. As a non-limiting example, each range discussed herein canbe readily broken down into a lower third, middle third and upper third,etc. As will also be understood by one skilled in the art all languagesuch as “up to,” “at least,” “greater than,” “less than,” and the likeinclude the number recited and refer to ranges which can be subsequentlybroken down into subranges as discussed above. Finally, as will beunderstood by one skilled in the art, a range includes each individualmember. Thus, for example, a group having 1-3 cells refers to groupshaving 1, 2, or 3 cells. Similarly, a group having 1-5 cells refers togroups having 1, 2, 3, 4, or 5 cells, and so forth.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopeand spirit being indicated by the following claims.

1. A method for removing sodium tripolyphosphate from a waste liquid,the method comprising: adding a phosphate binder to the waste liquid tocause the sodium tripolyphosphate to adsorb to the phosphate binder; andaerating the waste liquid to form bubbles in the waste liquid and tocause particles of the phosphate binder having the sodiumtripolyphosphate adsorbed thereto to adhere to the bubbles and rise to atop surface of the waste liquid.
 2. The method of claim 1, wherein thephosphate binder comprises a carbonate.
 3. The method of claim 2,wherein the phosphate binder comprises calcium carbonate.
 4. The methodof claim 1, wherein the phosphate binder comprises a salt of at leastone of magnesium, lanthanum, nickel, cadmium, iron, zinc, cobalt,strontium, barium, or manganese.
 5. The method of claim 1, wherein thephosphate binder comprises calcium acetate, magnesium carbonate,lanthanum carbonate, nickel carbonate, cadmium carbonate, ironcarbonate, zinc carbonate, cobalt carbonate, strontium carbonate, bariumcarbonate, manganese carbonate, or mixtures thereof.
 6. The method ofclaim 1, wherein the phosphate binder is added to the waste liquid priorto aerating the waste liquid.
 7. The method of claim 1, wherein aeratingthe waste liquid comprises bubbling air, oxygen, or nitrogen into thewaste liquid.
 8. The method of claim 1, further comprising removing theparticles from the top surface of the waste liquid.
 9. The method ofclaim 1, wherein the waste liquid is waste detergent water. 10-18.(canceled)
 19. A computer-readable medium having stored thereon,computer-executable instructions that, as a result of execution by anapparatus for removing sodium tripolyphosphate from a waste liquid,cause the apparatus to perform a method comprising: adding a phosphatebinder to the waste liquid including the sodium tripolyphosphate tocause the sodium tripolyphosphate to adsorb to the phosphate binder; andaerating the waste liquid to form bubbles in the waste liquid and tocause particles of the phosphate binder having the sodiumtripolyphosphate adsorbed thereto to adhere to the bubbles and rise to atop surface of the waste liquid.
 20. The computer-readable medium ofclaim 19, wherein the instructions, in response to execution by theapparatus, further cause the apparatus to route the waste liquid to theapparatus and control the routing and the adding such that the phosphatebinder is added to the waste liquid prior to aerating the waste liquid.